<script setup>
import { useMouseInElement } from '@vueuse/core';
import { ref, watch } from 'vue';

// 图片列表

const props = defineProps({
	imageList: {
		type: Array,
		default: [
			"https://yanxuan-item.nosdn.127.net/d917c92e663c5ed0bb577c7ded73e4ec.png",
			"https://yanxuan-item.nosdn.127.net/e801b9572f0b0c02a52952b01adab967.jpg",
			"https://yanxuan-item.nosdn.127.net/b52c447ad472d51adbdde1a83f550ac2.jpg",
			"https://yanxuan-item.nosdn.127.net/f93243224dc37674dfca5874fe089c60.jpg",
			"https://yanxuan-item.nosdn.127.net/f881cfe7de9a576aaeea6ee0d1d24823.jpg"
		]
	}
});

// 1.小图切换大图显示
const activeIndex = ref(0);

function mouseEnterFn(i) {
	activeIndex.value = i;
}

// 2. 获取鼠标相对位置
const target = ref(null);
const { elementX, elementY, isOutside } = useMouseInElement(target);


// 3. 控制滑块跟随鼠标移动（监听elementX/Y变化，一旦变化 重新设置left/top）
const left = ref(0);
const top = ref(0);
const positionX = ref(0);
const positionY = ref(0);

watch([elementX, elementY, isOutside], () => {

	if (isOutside.value) {
		return;
	}
	console.log("elementX, elementY变化");
	// console.log("isOutside = " + isOutside.value);
	if (elementX.value >= 100 && elementX.value <= 300) {
		left.value = elementX.value - 100;
	}
	if (elementY.value >= 100 && elementY.value <= 300) {
		top.value = elementY.value - 100;
	}

	if (elementX.value > 300) left.value = 200;
	if (elementY.value > 300) top.value = 200;
	if (elementX.value < 100) left.value = 0;
	if (elementY.value < 100) top.value = 0;

	positionX.value = -2 * left.value;
	positionY.value = -2 * top.value;
});
</script>


<template>
	<div class="goods-image">
		<!-- 左侧大图-->
		<div class="middle" ref="target">
			<img :src="props.imageList[activeIndex]" alt="" />
			<!-- 蒙层小滑块 -->
			<div class="layer" :style="{ left: `${left}px`, top: `${top}px` }" v-show="!isOutside"></div>
		</div>
		<!-- 小图列表 -->
		<ul class="small">
			<li v-for="(img, i) in props.imageList" :key="i" @mouseenter="mouseEnterFn(i)"
				:class="{ active: i === activeIndex }">
				<img :src="img" alt="" />
			</li>
		</ul>
		<!-- 放大镜大图 -->
		<div class="large" :style="[
			{
				backgroundImage: `url(${props.imageList[activeIndex]})`,
				backgroundPositionX: `${positionX}px`,
				backgroundPositionY: `${positionY}px`,
			},
		]" v-show="!isOutside"></div>
	</div>
</template>

<style scoped lang="scss">
.goods-image {
	width: 480px;
	height: 400px;
	position: relative;
	display: flex;

	.middle {
		width: 400px;
		height: 400px;
		background: #f5f5f5;
	}

	.large {
		position: absolute;
		top: 0;
		left: 412px;
		width: 400px;
		height: 400px;
		z-index: 500;
		box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
		background-repeat: no-repeat;
		// 背景图:盒子的大小 = 2:1  将来控制背景图的移动来实现放大的效果查看 background-position
		background-size: 800px 800px;
		background-color: #f8f8f8;
	}

	.layer {
		width: 200px;
		height: 200px;
		background: rgba(0, 0, 0, 0.2);
		// 绝对定位 然后跟随咱们鼠标控制left和top属性就可以让滑块移动起来
		left: 0;
		top: 0;
		position: absolute;
	}

	.small {
		width: 80px;

		li {
			width: 68px;
			height: 68px;
			margin-left: 12px;
			margin-bottom: 15px;
			cursor: pointer;

			&:hover,
			&.active {
				border: 2px solid $xtxColor;
			}
		}
	}
}
</style>